Lapping machine



Dec. 14 1926. 1,610,527 H. s. INDGE LAPPING MACHINE Filed Sept. 5, 1924 4 Sheets-Sheet 1 ilt-:1 7/ I Dec. l4 1926. 1,610,527

H. s. INDGE LAPPING MACHINE Filed Sept. 5, 1924 4 Sheets-Sheet 5 Dec. 14 1926.

. 1,610,527 H. s. INDGE LAPPING MACHINE Fire Sept. 5, 1924 4 Sheets-Sheet 4 Patented Dec. 14, 1926. l i i UNITED STATES PATENT OFFICE.

HERBERT STUART INDGE, OF WESTBORO, MASSACHUSETTS, ASSIGNOR TO BETIHEL- PLAYER 00., OF WESTBORO, MASSACHUSETTS, COPARTNERSHIP CONSISTING- OF JOSEPH N. BETHEL AND SIDNEY PLAYER.

LAPPING MACHINE.

Application filed- September 5. 1924. Serial No. 736,152.

This invention relates to a machine deor level in the surfaces to be lapped. Power signed for lapping either fiat or cylindrical may be supplied to the machine in any conwork and is of the type in which the work is venient manner, as by tight and loose pul- 65 positioned between a fixed and a positively leys 17 and 18 driven by a belt (not shown) rotated lap. and controlled by a shipper lever 19.

It is the object of my invention to pro- In the form of my invention shown in vide an improved mechanism for giving the Figs. 2 to 5, the shaft 20 which is driven by work holder certain positive and predeterthe pulley 17 is provided with a worm 21 60 mined movements relatively to the fixed and (Fig. 2) engaging a worm wheel 22 fixed movable laps. to a sleeve or cylindrical shell 23 having A further object is to provide means by upper and lower bearings in the bed 10. At which the location of movement of the work its upper end, the sleeve 23 carries a spider will be progressively changed relatively to or frame 2 1 to which is bolted the rotatable 66 the laps, so that the work will be brought lap 25. The spider 24; andlap 25 are supinto engagement with all parts of the lapported in fixed vertical position by a thrust ping surfaces. bearing 26 between the spider 2 4 and the My invention further relates to arrangeupper fixed bearing of the sleeve 23. ments and combinations of parts which will A work holder 30 is mounted between the o be hereinafter described and more particufixed lap 16 and the rotatable lap 25 and is larly pointed out in the appended claims. provided with recesses adapted to receive the Two forms of the invention are shown in work to be lapped. In Figs. 2 and 3, I have the drawings in which indicated a work holder 30 having circular Fig. 1 is a side elevation of a lapping marecesses or openings 31 to receive cylindrical chine embodying one form of my invention; blocks which are to be lapped upon their Fig. 2 is a partial sectional side elevation parallel end surfaces. In Fig. 4, I have inof that form of my invention shown in dicated a work holder having openings Fig. 1; x 32 for cylindrical pieces of work which are Fig. 3 is a detail plan View, partially to be lapped upon their convex surfaces. 80 broken away, and taken along the line 33 These openings 32 are preferably arranged 30 in Fig. 2; at an angle to a radius drawn therethrough. Fig. 1 is a view similar to Fig. 3 but show- I will now describe the special mechanism ing a work holder for cylindrical work; which I have provided for gyrating the Fig. 5 is a diagrammatic view-showing the work holders 30 or 30 and at the same time 6 path of movement of the work; orogressivcly changing the relation of the Fig.- 6 is a partial sectional side elevation work to the fixed and rotatable laps. For showing a second form. of my invention; this purpose I have provided a head 33 ro- Fig. 7 is a sectional plan view taken along tatable within and above the spider 24 and the line 77 in Fig. 6; and fixed to an inner sleeve 35 which is rotatable v Fig. 8 is a sectional view taken on the line in bearings within the sleeve 23 and which 88 in Fig. 4. has a spur gear 36 fixed to the lower end The general appearance of one form of thereof. A corresponding spur gear 37 is my improved machine is indicated in Fig. fixed to the lower end of the sleeve 23 and 1, in which I have shown a base or'bed 10 is connected to the gear 36 through interhaving a post or standard 11 on which a mediate gears 38 and 39 mounted on a stud head 12 is mounted for both vertical and 40 fixed in the base 10.

angular adjustment. A rack bar 13 is ve'r- Theratio of the gearing may be varied as tically adjustable in abearing 14 at the outer desired but, as shown herein, the gears 37 end of an arm 15 carried by the head 12. A and 38 are of equal size and the gear 39 is fixed or non-rotatable lap 16 is secured to the half as large as the gear 36. With this comlower end of the rack bar 13, preferably bination of gears, the head 33 will rotate by a connection which permits the lap 16 in the same direction as the spider 24 but at to adjust itself to slight variations in height only one half of the speed.

A series of three or more studs 41 are fixed in the head 33 androtatably support a series of pinions 42 which all simultaneously engage a spur gear 43 fixed to a non-rotatable shaft 44 which is secured at its lower end to a portion 45 of the bed 10. As the head 33 is positively rotated at one-half of the speed of the lap 25, carried positively around the periphery of the fixed gear 43 and are thus caused to rotate upon their own axes as well as being moved around the axis of the shaft 44 by rotation of the head 33.

Studs or crank pins -50 are mounted in blocks 51 which, are slidably adjustable radially on the enlarged hubs 52 of the pinone half as great ions 42. A cover-plate 53 encloses the gear 43 and pinions 42 and protects them from dust and dirt.

The crank pins 50 engage openings in the work holder 30 at three or more different points and positively turn the work holder about the axis of the shaft 44 and at a speed as the speed of the lap 25. At'the same time the work holder 30 receives a constant gyrating movement through the revolution of the pinions 42 upon. their own axes. If the number of teeth in the fixed gear 43 is not an exact multiple of the number of teeth in the pinions 42, the gyrations will not occur at exactly the same portions of the laps 16 or 25 on successive revolutions of the head 24 but will be advanced or retarded in position, according to the tooth ratio. By changing the ratio. between the pinions 42 and the gear 43 the number of gyrations for each revolution of the head 24 and the amount of progressive change in position of gyration for each revolution may be varied as desired.

In Fig. 5, I have indicated the path traced by a point at the center of oneof the recesses 31 as it is gyrated and advanced in the machine by the gearing described and shown. It will be noted at 54 (Fig. 5) that the orbit or path of travel is.not completed at exactly the same point on the'fixed lap at which it began but that the successive paths of travel will be successively'advanced relatively to those already formed.

Provision for adjusting the crank pins 50 to vary the throw thereof is clearly indicated in Figs. 3 and 4, the blocks 51 having elongated slots therein through which extend clamping screws which bind the blocks to the hubs 52 in any desired radial position. With this construction, the articles in the work holder 30 may be moved back and forth across any portion of the width of the annular lapping surfaces of the laps 16 and 25.

In Figs. 6 and 7, I have indicated a simplified form of my invention by which substantially the same results may be attained. In this form of my invention the movable lap the pinions 42 are is bolted to a spider or frame 61 fixed to a vertically extending hollow shaft 62. At the lower end of the shaft 62 any suitable driving connections such as a pulley 63 and belt 63" may be provided.

A head 64 is mounted for free rotation within and abote the spider 61 and is provided with studs 65 on which pinions 66 are rotatably mounted. The pinions 66 support adjustable blocks 67 having studs or crank pins 68 extending into openings in the work holder 69, as in the previous form of my invention. A gear 70 is mounted on the upper end of a fixed shaft 71 and engages the several pinions 66 about its periphery. An annular internal gear 72 is mounted on the spider 61 to rotate therewith, and engages the pinions 66 upon the outer surfaces thereof. Acover 73 is supported on the head 64 and protects the gears 66, 70 and 72.

lVhen the hollow shaft or sleeve 62 and spider 61 are positively rotated by the pulley 63, the ring gear '(2 is rotated therewith and causes the pinions 66 to travel around the periphery of the fixed spur gear 70. In this manner the crank pin or studs 68 are rotated about the axes of the pinions and are also progressively advanced relatively to the fixed and movable laps. The resultant path of movement of the work depends upon the gear ratios and may be substantially similar to that already described, and shown dia grammatically in Fig. 5.

W hen using either form of my invention for cylindrical or conical work, it is necessary that the work holder 30 be free to revolve upon its own axis at a speed determinedby the rolling of the cylinders upon the fixed lap (see Figs. 4 and 8). To permit such free rotation, I insert a carrierplate 75 between the driving studs or crank pins 50 and the work holder 30. This carrier plate 75 has openings 76 to receive the studs 50 and has a central stud 77 on which the work holder 30 is loosely fitted. The studs 50 are preferably somewhat shorter than the studs 50 in the regular form of the machine and do not project above the top surface of the fixed lap 25. When thus mounted, the work holder 30 receives an ec centric movement from the studs 50 but is also free to rotate about its center on the stud 77.

Having thus described two forms of my invent-ion, it will be seen that 1 have provided a lapping machine in which the work holder has a general movement in a positive and predetermined relation to the movement of the rotatable lap and in which the work holder is also gyrated or moved transversely in such a way that the work is moved back and forth across the face of the laps to engage the entire working surface thereof. In this way the full value of the entire lapping surface is utilized.

of said Having thus described two forms of my invention I do not wish to be limited to the details herein disclosed otherwise than as set forth in the claims, but what I claim is 1. A lapping machine having a fixed lap, a positively rotated lap, a work holder mounted between" said laps, and means to rotate said work holder and to give said holder a plurality of positive and definite gvratin movements durin each rotation holder relative to said fixed lap. I

2. A lapping machine having a fixed lap, a positively rotated lap, a rotatable work holder mounted between said laps, devices rotatable about a plurality of parallel axes eliective to give sald work holder a plurality of positive and definite gyrating movements during each rotation of said work holder, and positive means to progressively advance said devices relatively to the fixed lap, thereby rotating said holder.

3. A lapping machine having a lixed'lap, a rotatable lap, a work holder mounted between said laps, means to give said work holder definite gyrating movements about a plurality of parallel axes, means to progrezsively advance said axes relatively to the fixed lap, and means to permit adjustment of theextent of said gyrating movements.

4. A lapping machine having a fixed lap, a positively rotated lap, a work holder mounted between said laps, a rotatable head, means to drive said head and rotatable lap in a definite speed relation, a gear mounted in fixed position concentric with said head, a plurality of pinions mounted on said head on parallel axes eccentric to the axis of said head, and crank pins on said pinionseiiective to gyrate positively said work holder, said pinions being also continuously ad vanced by the rotation of said head to positively rotate said work holder.

5. A lapping machine having a fixed lap, a rotatable lap, a work holder mounted be; tween said laps, a rotatable head, means to drive said head and rotatable lap in a definite speed relation, a gear fixed in position concentric with said head. a plurality of pinions mounted on parallel axes eccentrlc to the axis of said head, 'crankplns on said pinions eliective to gyrate and rotate said work holder, and means to permit adjustment of the throw of said crankpins.

6. A lapping machine having a. fixed lap,

a positively rotated lap, a work holder mounted between said laps, a freely rotatable head, in'ions mounted on said head at points space from the axis thereof, crankpms on said pinions engaging said work holder to gyrate and rotate the same, a fixed ear simultaneously engaging all of said pinions 'at one point thereof, and a driven gear engaging said pinions at other points thereof to positively rotate said pinions and also progressively advance the same relative to the fixed gear.

7. A lapping machine having a fixed lap, a positively rotated lap, a work holder mounted between said laps, a freely rotatable head, pinions mounted on said head at points spaced from the axis thereof, crankpins on said pinions engaging said work holder'to gyrat'e and rotate the same, a spur gear engaging each of said'pinions, an internal gear also engaging each of said pinions, and means to drive one of said gears.

S. A lapping machine having a fixed lap, a positively rotated lap, 'a work holder mounted between said laps, a 'freely rotatable head, pinions mounted on said head at points spaced from the axis thereof, crankpius on said pinions enga ing said work holder to gyrate and rotate 516 same, a fixed spur gear engaging each of said pinions,.an internal ring gear also engaging eachiof said pinions, and means to positively rotate said internal gear.

9. A lapping machine having a fixed lap, a positively rotated lap, at work holder mounted between said laps', a freely rotatable head, pinions mounted on said head at points spaced from the axis thereof, crankpins on said pinions engaging said work holder to gyrate and rotate the same, a fixed s'pur gear engaging each of said pinions, an internal ring gear also engaging each of said pinions, and means to simultaneously rotate said internal gear and said rotatable lap.

In testimony whereof I have hereunto aflixed my signature.

HERBERT S. INDGBI 

